Concept:The word “alight” means to get off or step down from a vehicle.
The question asks for the word that is opposite in meaning to “alight.”
Explanation:To alight from a station or vehicle means to leave or get down.
For example, a passenger alights from a bus when the journey ends.
The opposite action is to get onto a vehicle, which is called “boarding.”
Option A, “ascends,” means to go up, not to get onto a vehicle.
Option C, “enters,” means to go inside a place, but it does not specifically mean getting on a bus or train.
Option D, “joins,” means to become part of a group, which is not related here.
Therefore, the best opposite of “alights” in this context is “boards.”
Answer:B. boards